Special feeding mechanism for working table of silicon carbide slicing machine

Abstract

The invention discloses a special feeding mechanism for a workbench of a silicon carbide slicing machine. A lead screw is mounted on a main body rack; the workbench rack is arranged on one side of the main body rack and connected to the lead screw through a sliding block and a lead screw nut, and the workbench rack can be driven to move up and down through rotation of the lead screw. The SiC crystal ingot is pasted on the knife rest, and the whole knife rest pasted with the SiC crystal ingot is installed on the working table rack and moves along with movement of the working table rack. The servo motor is fixedly connected with the clutch speed reducer and then mounted on the other side of the main body rack, and the clutch speed reducer is connected with the lead screw through the synchronous belt and the belt wheel after mounting and fixing are completed, so that the servo motor can drive the workbench rack to feed; the clutch speed reducer is internally provided with an automatic switching function and is controlled through a PLC program after wiring, high-precision stable feeding in the machining process at a low gear can be guaranteed, debugging and rapid feeding of blanking and tool retracting can be conveniently conducted at a high gear, and tool retracting can be completed within 2 min.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment, and in particular to a special feeding mechanism for a silicon carbide slicer workbench, and to the precision of slicing a silicon carbide crystal ingot (SiC crystal ingot), and in particular to ensuring high-precision low-speed feeding during the cutting process. Background Art

[0002] With the vigorous development of the semiconductor industry, semiconductor materials have evolved from the first generation to the third generation. The first generation of semiconductor materials, represented by silicon, has a power of about 100W, but a frequency of only about 3GHz; the second generation, represented by gallium arsenide, has a power of less than 100W, but a frequency of 100GHz. Therefore, the first two generations of semiconductor materials are more complementary to each other. The third generation of semiconductors, represented by gallium nitride and silicon carbide, have a power of more than 1000W and a frequency close to 100GHz. The advantages are very obvious, so they may replace the first two generations of semiconductor materials in the future. These advantages of the third generation of semiconductors are largely due to one point: they have a larger bandgap width than the first two semiconductors. It can even be said that the main distinguishing indicator between the three generations of semiconductors is the bandgap width. Because of the above advantages, the third generation of semiconductor materials can meet the requirements of modern electronic technology for harsh environments such as high temperature, high pressure, high power, high frequency and high radiation, so they can be widely used in cutting-edge industries such as aviation, aerospace, photovoltaics, automobile manufacturing, communications, and smart grids. At present, it is mainly used to manufacture power semiconductor devices. With the changes in semiconductor materials, extremely high requirements are placed on SiC wafer TTV (total thickness deviation) and Warp (warpage), and ensuring the feed accuracy of the workbench for cutting SiC crystal rods has become a major problem. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a special feeding mechanism for a silicon carbide slicer worktable, which realizes high-precision and low-speed feeding of the slicer worktable and solves at least one of the above problems.

[0004] The technical solution of the present invention is: a special feeding mechanism for a silicon carbide slicer worktable, comprising a main frame, a servo motor, a clutch reducer, a synchronous belt, a lead screw, a worktable frame and a tool holder;

[0005] The lead screw is mounted on the main frame;

[0006] The workbench frame is arranged on one side of the main frame, and is connected to the lead screw through a slider and a lead screw nut, and can drive the workbench frame to move up and down through the rotation of the lead screw;

[0007] The SiC ingot is attached to the tool holder, and the tool holder attached with the SiC ingot is integrally mounted on the workbench frame and moves with the movement of the workbench frame;

[0008] The servo motor is connected and fixed to the clutch reducer and then installed on the other side of the main frame. After the installation and fixing is completed, the clutch reducer is connected to the lead screw through a synchronous belt and a pulley to complete the servo motor driving the workbench frame feeding action; the clutch reducer has a built-in automatic switching function, and is controlled by a PLC program after wiring, which can ensure high-precision and stable feeding of the processing process in low-speed gear, and facilitate debugging and fast feeding of material removal and retraction in high-speed gear, and the retraction can be completed in 2 minutes.

[0009] Furthermore, it also includes an accordion protective cover, which is arranged on the workbench frame to prevent powder and oil generated during the cutting process from entering the workbench frame, thereby reducing damage to precision parts such as bearings and lead screws.

[0010] Furthermore, the lead screw is installed on the main frame through bearings and pressure blocks.

[0011] The beneficial effects of the present invention are:

[0012] (1) The worktable feed mechanism reducer adopts a clutch reducer, which is convenient for debugging and rapid lifting during unloading;

[0013] (2) The reducer and the worktable feed screw are connected by a synchronous belt to ensure stable operation and reduce vibration;

[0014] (3) The worktable feed mechanism uses multi-stage deceleration to ensure stable and accurate feeding at a low speed of 0.015 mm / min.

[0015] Due to the particularity of SiC materials, it is highly brittle and has high hardness. The stability requirements for the processing equipment are higher. In order to ensure the TTV and Warp of SiC wafers, continuous low-speed cutting is required for 120 hours or more. Therefore, it is necessary to ensure the stability of each mechanism of the equipment, especially the high-precision and stable low-speed feeding (0.015mm / min) of the workbench feeding mechanism. At the same time, due to production needs, it is necessary to quickly return to the processing zero position after the cutting is completed. At this time, the feeding mechanism needs to feed quickly. The present invention adopts a clutch reducer, which can switch between high and low speed feeding, solves the problem of fast feeding, and can reach 150mm / min in the fast state. The workbench feeding mechanism lead screw and the reducer are connected by a synchronous belt to ensure that the lifting and lowering of the workbench is synchronized with the motor output. Compared with gear connection, coupling connection, etc., it can effectively reduce the vibration of the motor operation transmitted to the workbench, and also reduce the maintenance cycle and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a specific structural schematic diagram of the present invention.

[0017] Figure 2 for Figure 1 Cross-sectional view along the AA direction.

[0018] In the figure: 1. main frame, 2. servo motor, 3. clutch reducer, 4. synchronous belt, 5. lead screw, 6. workbench frame, 7. accordion protection cover, 8. tool holder, 9. SiC ingot. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] like Figure 1 , 2 As shown, a special feeding mechanism for the worktable of a silicon carbide slicer includes a main frame 1, a servo motor 2, a clutch reducer 3, a synchronous belt 4, a lead screw 5, a worktable frame 6, an accordion protective cover 7 and a tool holder 8. The lead screw 5 is installed on the main frame 1 through bearings, pressure blocks (not shown), etc.; the worktable frame 6 is arranged on one side of the main frame 1, and is connected to the lead screw through a slider and a lead screw nut, and the worktable frame 6 can be driven up and down by the rotation of the lead screw; the SiC ingot 9 is pasted on the tool holder 8, and is installed on the worktable frame as a whole, and moves with the movement of the worktable frame; the accordion protective cover 7 prevents powder and oil generated during the cutting process from entering the inside of the worktable frame 6, and reduces damage to precision parts such as bearings and lead screws; the servo motor 2 is connected and fixed to the clutch reducer 3 and then installed on the other side of the main frame 1. After the installation and fixing is completed, it is connected to the worktable frame 6 through the synchronous belt 4, The pulley (picture omitted) connects the reducer to the lead screw to complete the feeding action of the workbench frame driven by the servo motor; the clutch reducer 3 has a built-in automatic switching function, which is controlled by the PLC program after wiring to ensure high-precision and stable feeding of the processing process in low-speed gear, and convenient debugging and fast feeding of unloading and retracting in high-speed gear, and the retracting can be completed in 2 minutes at the fastest; the ordinary reducer connection method can only meet one of the above. The one with low reduction ratio and fast feeding speed will be fast and slow at ultra-low speed operation, which is not conducive to cutting. The one with high reduction ratio and slow feeding speed will be very slow in unloading, retracting and debugging, and it will take 5-10 hours to complete the retracting at the highest speed, which is not conducive to production. After multiple experimental tests of the WSS300 slicer, all the data of the cut wafers are very good.

[0021] Due to the particularity of SiC materials, it is highly brittle and has high hardness. The stability requirements for the processing equipment are higher. In order to ensure the TTV and Warp of SiC wafers, continuous low-speed cutting is required for 120 hours or more. Therefore, it is necessary to ensure the stability of each mechanism of the equipment, especially the high-precision and stable low-speed feeding (0.015mm / min) of the workbench feeding mechanism. At the same time, due to production needs, it is necessary to quickly return to the processing zero position after the cutting is completed. At this time, the feeding mechanism needs to feed quickly. The present invention adopts a clutch reducer, which can switch between high and low speed feeding, solves the problem of fast feeding, and can reach 150mm / min in the fast state. The workbench feeding mechanism lead screw and the reducer are connected by a synchronous belt to ensure that the lifting and lowering of the workbench is synchronized with the motor output. Compared with gear connection, coupling connection, etc., it can effectively reduce the vibration of the motor operation transmitted to the workbench, and also reduce the maintenance cycle and cost.

[0022] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A special feeding mechanism for a silicon carbide slicer worktable, characterized by: It comprises a main frame (1), a servo motor (2), a clutch reducer (3), a synchronous belt (4), a lead screw (5), a workbench frame (6) and a tool holder (8); The lead screw (5) is mounted on the main frame (1); The workbench frame (6) is arranged on one side of the main frame (1), and is connected to the lead screw (5) via a slider and a lead screw nut, and can drive the workbench frame (6) to move up and down through the rotation of the lead screw; The SiC crystal ingot (9) is adhered to the tool holder (8), and the tool holder (8) adhered with the SiC crystal ingot (9) is integrally mounted on the workbench frame (6) and moves with the movement of the workbench frame; The servo motor (2) and the clutch reducer (3) are connected and fixed and then installed on the other side of the main frame (1). After the installation and fixing is completed, the clutch reducer (3) is connected to the lead screw (5) via a synchronous belt (4) and a pulley, so that the servo motor drives the workbench frame to feed. The clutch reducer (3) has a built-in automatic switching function and is controlled by a PLC program after wiring, so that high-precision and stable feeding of the processing process can be ensured in a low-speed gear, and fast feeding of material removal and retraction can be facilitated in a high-speed gear, so that retraction can be completed in 2 minutes.

2. The special feeding mechanism for a silicon carbide slicer worktable according to claim 1, characterized in that: It also includes an accordion protection cover (7), which is arranged on the workbench frame (6) and can prevent powder and oil generated during the cutting process from entering the workbench frame (6).

3. The special feeding mechanism for a silicon carbide slicer worktable according to claim 1, characterized in that: The lead screw (5) is mounted on the main frame (1) via a bearing and a pressure block.

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